Apparatus for self-administration of anesthetics



Dec. 26, 1939. J SHQLES AL 2,185,068

APPARATUS FOR SELF-ADMINISTRATION 0F ANESTHETICS Filed Dec. 10, 1937' 4 Sheets-Sheet 1 INVENTORS jasiq'n (2. Jim/es 011s .1 $2111: B 7 M'YMW km ATTORNEY Dec. 26, 1939. J. G. SHOLES ET AL 2,185,068

APPARATUS FOR SELF-ADMINISTRATION 0F ANESTHETICS Filed Dec. 10, 1957 4 Sheets$heet 2 INVENTORS BYL/WWWMM/ ATTQRNEYS Dec. 26, 1939. J. G. SHOLES ET AL APPARATUS FOR SELF-ADMINISTRATION 0F ANESTHETICS Filed Dec. 10, 1937 4 Sheets-Sheet 4 54m .5 m d my. m wa a J% Jr M0 J .M m

Patented Dec. 26, 1939 APEPARATUS FOR SELF-ADMINISTRATION OF ANESTHETIGS c Justin G. Sholcs, Cleveland, and Oris J. Smith, Cleveland Heights, Ohio, assignors to The Ohio Chemical and Manufacturing Company, Cleveland, Ohio, a corporation of Ohio Application December ll), 1937, Serial No. 179,060

Claims.

This invention relates to apparatus for the administration of an anesthetic gas or gases in which the patient himself controls the supply of gas to his lungs for the purpose of producing 5 analgesia, or, at most, no more than shallow anesthesia from which the patient speedily regains consciousness. It is to be understood that the terms gas and anesthetic are used herein to include a vapor as well as a gas strictly so called, and also a vapor or vapors, and mixtures wholly gaseous or vaporous, or gaseous and vaporous.

The chief object of the invention is to provide an apparatus in which the valve controlling the flow of gas will be automatically closed whenever the patient ceases to operate the controlmechanism or device, so that if he should become unconscious the valve will close and thus cut off the supply of gas regardless of the position of the control mechanism when he ceases to actuate it. Another object of the invention is to provide an improved apparatus of simple char acter, unfailing in operation, and capable of being manufactured at low cost. A further object is to provide an apparatus in which, under the control of the physician, dentist, or other attendant, another gas, say one of greater analgesic or anesthetic potency, or a resuscitating or a therapeutic gas, for example oxygen, can be administered when the attendant deems it desirable. Still another object is to provide an apparatus which is especially adapted for the administration of nitrous oxide or other anes thetic gas in dentistry and in surgical operations of a minor nature, as for example lancing a boil, setting a broken bone, or reducing a dislocation. To these and other ends the invention comprises the novel features of construction and combinations of elements hereinafter described.

Of the various constructions in which the invention can be embodied we have selected for illustration and specific description herein the one which is at the present time considered as exhibiting the invention in its most effective and advantageous form.

Referring now to the accompanying drawmgs:

Fig. l is a side view of the complete apparatus, the contractible and expansible rubber 50 and releases to control the supply of gas, shown bulb, which the patient alternately compresses on line 4--& of Fig. 2, of the patient-controlled valve mechanism, showing the valve in closed position. i

Fig. 5 is a sectional view of the reservoir portion of the apparatus provided for the admixture of air with the gas and for equalizingor stabilizing the flow of the thus mixed fluid to the mask.

Fig. 6 is a detail section of the mask designed for use in dentistry.

The apparatus illustrated comprises a sup-- porting standard iii mounted on casters and carrying at the top a tubular crosshead ll having yokes of conventional type l2, It to hold the bottles or cylinders i l, i5. Cylinder i5 is connected through one part of the crosshead to the pressure reducing valve It which is equipped with a high-pressure gauge ii to indicate the pressure in the cylinder when valve i8 is opened by turning the handle IQQand a low-pressure gauge it to indicate the pressure at the reducing-valve outlet, as determined by the adjustment of the valve by the handle 2!. The apparatus may also have further control means, to be operated or set by the doctor, as for example a needle valve 22 for controlling the rate of flow of the gas. This valve may have an off position, from which the valve is progressively opened to light, medium, and heavy positions, which may be marked onthe dial to signify the extent of the analgesia to'be'produced. Thus if it is observed that the patient operates the patient-controlled mechanismrapidly the doctor may set the valve 22 at light, to minimizethe possibility of the patient getting enough gas to cause him to lose consciousness;

and conversely the valve may be set at medium or heavy as the doctor may deem necessary to insure that enough gas will be delivered for effective analgesia in the case of a pa- .tient who is observed to operate the patientcontrolled valve mechanism slowly.

The cylinder it, which may, for instance, contain oxygen, is connected by the other part of the tubular cross-head M to valve 23 (operated by the doctor) and thence by a flexible tube 24 to the patient as hereinafter described.

The gas from valve 22 passes to the patientcontrol mechanism 25, which latter is connected by a flexible tube 26 to one arm of a Y or T fitting 2'! in the end of a flexible tube 28; tube 24!, from doctors valve 23, being attached to the other arm of the Y. Tube 28 leads to what we may term a reservoir or a mixing chamber since it serves to admit air and mix it with the gas and also serves to store more or less of the resulting mixture, usually under light pressure. This reservoir, connected to the flexible tube 23, comprises a corrugated non-collapsible tube 23, provided with a plurality of ports 3E3 foroutfiow of gas or air and gas to the light expansible balloon 3| surrounding the tube. At the inlet end of the tube is a check-valve comprising a thin flexible rubber disk 32 to permit inflow of air but prevent outflow from the tube, and at the other end is a similar valve 33 arranged to permit outflow but prevent inflow. The outlet end of the mixing reservoir is detachably connected by a pair of flexible rubber tubes 34 to a mask 35, which in the form illustrated is of a shape and size to fit over the patients nose, leaving the month free to be opened at will. At the reservoir the tubes are connected to the tube 29 by means of a bushing 36 releasably but firmly fitting the sleeve 31, and at the mask the tubes are detachably connected to the tubular inlets 38 by means of suitable fittings 3s. The mask 35 is equipped with an exhaling check valve 46. It will be seen that the check valve 40 prevents inhalation except through valve 33 and that the latter prevents exhalation into the reservoir.

The patient-controlled valve mechanism 25, shown in Figs. 1, 2, and 4, comprises a casing 45 conveniently made in cylindrical form, and at-- tached to the valve 22. The casing is divided by an interior partition or eptum it into a gas chamber 41 and a valve-operating chamber d3. Gas from the pressure-reducing valve 86 and doctors valve 22 enters the gas chamber 4! through a passage 49 formed in the partition 46 and terminating in a valve seat 5% to cooperate with a valve member 5! which is freely movable in the chamber but is urged-into closed position on the valve seat by an expansible coil spring 52 tensionedby compression between the valve and the cap 53 screw-threaded on the casing. The valve member may have a resilient insert 54 to bear on the edge of the valve seat to insure hermetic sealing of the gas passage 39 when the valve is closed. The gas chamber is provided with an outlet nipple 55 to which the tube 26, described above, is detachably fitted.

In the valve-operating chamber 48 is a valveactuating member in the form of a plate 56 equipped with pins or rods 57f guided smoothly and easily in openings in the partition so that when the member is advanced (i. e., toward the right in Fig. 4) the pins will pushthe valve member iii off the valve seat 583 against the tension of the valve-closing spring 52 and thus permit gas to flow from the gas inlet passage to the chamber and thence through nipple to tube 2%. The member or plate 56 is itself moved rightwardly by air pressure acting through the instrumentality of an expansible and collapsible means which is preferably a soft elastic rubber disk 53 having a peripheral flange 59 extending into a circumferential groove in the end of the valve casing. A cap 61!, screw-threaded on the casing, clamps the diaphragm on the edge of the casing to seal the chamber against the escape of gas entering the same along the pins 5?. The cap is provided with a nipple 6| for connection with a flexible rubber tube 62 at the other end of which is a rubber bulb 63. At the outer end of the bulb a check valve 6G is provided to prevent escape of air when the bulb is compressed but permitfree inflow of air as the bulb expands. At the other end of the bulb is a check valve 65 permitting free flow air to the tube 62 and thence to the valve-operating chamber 48 when the bulb is compressed but preventing back-flow from i the chamber to the bulb when the latter is released. The cap 68 is also provided with an air-vent for escape of air from behind (the left of) the diaphragm. This vent is preferably in the form of a short tube 68 having a transverse pas- I sage 6? close to the surface of the cap 60 to minimize accidental stoppage of the vent and make intentional stoppage by the fingers practically if not wholly impossible.

To insure firm and hermetic seating of valve;

member 5i on the seat 55) we prefer to have slight lost motion between the valve-opening means, in the present instance the plate 56 and pins 5?, so that the former can seat itself even if the plate and pins are in slightly advanced position. The

construction illustrated, in which the pins are not attached to the valve member, is also advantageous as facilitating assembly of the parts and permitting parts in one compartment or chamber to be removed without disturbing the parts in the other.

The operation of the apparatus is as follows:

The pressure-reducing valve or regulator it is opened by the doctor by means of handle 2!,

then valve 58, on the cylinder containing the anesthetic, is opened, causing the cylinder pres sure to be indicated on gauge i'l, after which the.

regulator or pressure-reducing valve is adjusted by the doctor, while compressing and releasing bulb 83 energetically, until the needle on gauge 20 swings to a suitable low point, which, in the case of nitrous oxide, may be about 5 pounds per square inch. The tubes 34 are then passed'overl the p-atients head and the mask is fitted over his nose, after which the sliding clamp iii, Fig. l,i is

pushed up toward the back of the head to a point I at which the soft flexible tubes hold the mask closely but comfortably in place. Desiring to prevent or relieve any pain that he may expect or feel, the patient compresses andreleases the bulb repeatedly. Compression forces air from the bulb and against the diaphragm 58, thus expanding the same against the plate 5 6 and moving-A the valve member 5! off the seat 59. Gas then flows through tubes 25 and 28 to the reservoir 2s e|, when a mixture of gas and air is drawn into the patients lungs as he inhales.

bulb vigorously and rapidly at first until he The patient is instructed to compress and release the' 1 experiences loss of sensation, and then to compress the bulb only occasionally as he feels the need for more gas;

the small air vent 66, but if rte-compression follows release promptly the valve can be held open,

At each compression, air leaks out from behind the diaphragm 58 through.

the outflow of air through vent he being too slow to permit the valve to close before the next impulse from the bulb. However, if the patient 6 despite the doctors instructions works thefbulb too rapidly, or because of unexpected sensitiveness to the gas, should become unconscious, the

resulting cessation of the pumping action will.

permit the valve to close, thus cutting off further flow of gas to the tube 26; and. it will be seen that this closing of the valve occurs no matter at what stage of compression or expansion the patient may holdthe bulb when he loses con-.

trated and described but can be embodied in other forms without departure from its spirit.

We claim:

1. In an apparatus for administration of an anesthetic gas under patient control, the combination with a source of anesthetic gas and an inhaling mask; of patient-operable means for controlling the delivery of gas to the mask, comprising a casing having an inlet connected to the source of gas and an outlet connected to the mask, a valve enclosed in the casing at one end thereof and movable longitudinally of the casing to control the flow of gas to the outlet, an actuating member housed in the casing and movable longitudinally thereof in one direction for opening the valve and in the opposite direction for closing the valve, patient-operable means comprising va flexible diaphragm across the casing at the end thereof opposite to the valve to move said member in the first mentioned direction and thereby open the valve and movable in the opposite direction to enable the valve to close, an air vent to afford such last mentioned movement of the flexible diaphragm and a spring cooperating with the valve to close the same.

2. In an apparatus for administration of an anesthetic gas under patient control, the combination with a source of anesthetic gas and an inhaling mask; of means for controlling the delivery of gas to the mask, comprising a casing having an inlet connected to the source of gas and an outlet connected to the mask, an inletv valve enclosed in the casing at one end thereof and movable longitudinally of the casing to control the flow of gas to the mask, a valve operating member enclosed in the casing at the other end thereof and reciprocable longitudinally of the casing, means intermediate to the movable member and the valve to open the latter by direct thrust on the same exerted longitudinally of the casing, patient-operable means including a flexible diaphragm sealed across the casing at the said other end thereof to move said member in one direction to exert direct thrust upon the inlet valve through said intermediate means and thereby open the valve, a spring cooperating with the valve to close the same and restore said valve operating member to initial position and an air vent from the casing to vent air from a space behind the diaphragm to allow the valve to close.

3. In a patient-controlled apparatus for administering an anesthetic gas, the combination of a casing adapted for connection with a source of anesthetic gas and having an outlet for connection with an inhaling mask, said casing having at one end a valve chamber and at the other end a valve operating chamber having a vent for gradual escape ocf air, a gas control valve housed in the valve chamber to reciprocate therein longitudinally of the casing, a valve-opening member housed in the other chamber to reciprocate therein longitudinally of the casing, means housed in the casing between said member and the valve and movable longitudinally of the casing in one direction from an initial position to shift the valve in the same direction and thereby open the same for delivery of gas to theoutlet, said means being also movable in the other direction, an expansible resilient diaphragm arranged in the valve operating chamber between the said air vent and the valve-opening member to seal the latter chamber against escape of gas and by its expansion shift the valve-opening member from its initial position, a resilient pneumatic. bulb connected with the valve operating chamber for compression by the patient to expand the resilient diaphragm, and a spring housed in the valve chamber and cooperating with the valve to close the same and restore the valve-opening member to its initial position as air escapes through said vent.

4. In a patient-controlled apparatus for administering an anesthetic gas, the combination of a casing adapted for connection with a source of anesthetic gas and having an outlet for connection with an inhaling mask applied to the patients face, said casing having a partition dividing it into a valve chamber at one end and at the other end a valve operating chamber having a vent for gradual escape of air, a gas control valve housed in the valve chamber to reciprocate therein longitudinally of the casing, a valve-opening member housed in the other chamber to reciprocate therein longitudinally of the casing, rod means housed in the casing between said member and the valve and. movable longitudinallyof the casing through said partition in one direction to shift the valve in the same direction for delivery of gas from the inlet to the outlet, said rod means being movable in the other direction to enable the valve to close, an expansible resilient diaphragm arranged in the valve operating chamber between the said air vent and the valve-opening member to seal the latter chamber against escape of gas and by its expansion shift the valve-opening member from its initial position, a resilient pneumatic bulb connected with the valve operating chamber for compression by the patient to expand the resilient diaphragm, and a spring housed in the valve chamber and cooperating with the valve to close the same and restore'the valve-opening member to its initial position as air escapes through said vent.

5. In a patient-controlled apparatusfor administering an anesthetic gas, the combination of a casing adapted for connection with a source of anesthetic gas and an outlet for connection with an inhaling mask applied to the patients face, said casing having at one end a valve chamber and at the other end a valve operating chamber having a vent for gradual escape of air, a gas control valve housed in the valve chamber to reciprocate therein longitudinally of the casing, a valveopening member housed in the. other chamber to reciprocate therein longitudinally of the casing and having a plurality of rods to cooperate with the valve to shift the latter longitudinally of the casing and thereby open the valve for delivery of gas to the outlet, an expansible elastic diaphragm spanning the valve operating chamber between the said air vent and the valve-opening member to seal the casing against escape of gas and by its expansion shift the valve-opening member from its initial position, a resilient compressible and expansible pneumatic bulb connected with the valve operating chamber for compression by the patient to expand the diaphragm, and a spring housed in the valve chamber and cooperating with the valve to close the same and restore the valve-opening member to its initial position as air escapes through said vent.

JUSTIN G. SHOLES. ORIS J. SMITH. 

